Mechanisms of Antimicrobial Action and Resistance 3

Question 0

Telavancin (Vibativ)

Answer 0

Glycopeptide derivative of vancomycin
Treatment of complicated skin infections by gram positives
Effective against MRSA but not VRSA or VRE
IV administration

Question 1

Retapamulin (Altabax)

Answer 1

New drug class, product of fungi fermentation
Approved by FDA in 2007 for treatment of impetigo caused by S. pyogenes and Methicillin sensitive S. aureus
May be effective against MRSA
Topical ointment

Question 2

Dalbavancin (Dalvance)

Answer 2

Lipoglycopeptide
Inhibits cell wall synthesis
For complicated skin infections and suture infections by gram positives
Effective against MRSA but not VRSA or VRE
IV admin

Question 3

Tedizolid (Sivextro)

Answer 3

Oxazolidinone
Inhibits protein synthesis
Skin infections and suture infections by gram positives
MRSA but not VRSA or VRE
Oral/IV

Question 4

Oritavancin (Orbactiv)

Answer 4

Oxazolidinone
Inhibits protein synthesis
Skin and skin suture infections by gram positives
MRSA but not VRSA or VRE
IV admin

Question 5

Fidaxomicin (Dificid)

Answer 5

Macrolide
Clostridium difficile diarrhea in 18 years +
Oral admin with minimal systemic absorption

Question 6

There have been no development of drugs to treat what kind of bacteria for almost 5 decades now?

Answer 6

Gram negative bacilli

Question 7

MRSA infects and kills how many per year?

Answer 7

Infects greater than 94k

Kills greater than 19k

Question 8

How much is antibiotic resistance costing us?

Answer 8

$21-34 billion a year

Question 9

NDM-1 E. coli and Klebsiella

Answer 9

New Delhi metallo-beta-lactamase-1
Spread from India to UK/US
All strains resistant to all antibiotics except tigecycline or colistin (10% of strains are resistant to those too)

Question 10

In general hospital sewers, what % of bacteria are resistant to streptomycin and tetracycline?

Answer 10

34.7%

32%

Question 11

Shift in treatment of sore throats?

Answer 11

Less use of penicillin and erythromycin

More use of extended-spectrum macrolides and fluoroquinolones

Question 12

What is the only cause of sore throat that is antibiotic warranted? What percent are penicillin sensitive?

Answer 12

Group A beta-hemolytic streptococci
Which is only cultured 5-17% of cases
85-95% are penicillin sensitive

Question 13

Presentation of what symptoms are required for treatment WITHOUT TESTING for Group A beta-hemolytic streptococci?

Answer 13

Cough, runny nose, hoarse voice, diarrhea, mouth sores

Question 14

Presentation with sudden onset of sore throat, painful swallowing, fever?

Answer 14

Should be tested with a rapid antigen test before prescribing antibiotics

Question 15

What are 4 societal contributors to antibiotic resistance?

Answer 15

Antibiotic additives in stock feed
Chlorine treatment in water (bacteria that survive are resistant)
Mercury and other contaminants in water (same ^)
Antibacterial soaps

Question 16

Two ways that we can maintain therapeutic levels?

Answer 16

Avoid use of drugs when MIC is at or only slightly below the attainable level
Prevent biofilms and treat them aggressively

Question 17

3 novel antibacterial sources?

Answer 17

Peptides from higher organisms
Steroids from higher organisms
Inhibitors of additional pathways that block lipid A synthesis (important for gram negative outer membranes)

Question 18

What is magainin?

Answer 18

Peptide from frogs, didn’t make the cut

Question 19

What is squalamine?

Answer 19

Steroids from sharks

Question 20

What are the ESKAPE bacteria?

Answer 20

Enterococcus (VRE)
S. aureus (MRSA)
Klebsiella
Acinetobacter
Pseudomonas
ESBL (E. coli, enterobacter)

Question 21

Of the ESKAPE bacteria, which three are resistant to almost all antibiotics? Which are resistant to all oral antibiotics?

Answer 21

Klebsiella, Acinetobacter, Pseudomonas

EBSL (E. coli, enterobacter)